Which geo-projection to use for odometry [closed]

Question

I would like to make a little survey regarding the (geo)spatial projection that you use when elaborating your GPS and movement data for the spatial awareness of your robots.

Moving all GPS coordinates to a planar projection seems to be the more reasonable choice since not only distances (for which several formulas and approximations exist), but bearings must be computed.

Generally, although scales are pretty small here, avoiding equirectangular approximation seems a good idea in order to keep a more consistent system.

Avoiding working in the 3D world (Haversine and other great-circle stuff) is probably a good idea too to keep computations low-cost.

Moving the world to a 2D projection is hence what seems to be the best solution, despite reprojection of all input GPS coordinates is needed.

I would like to get opinions and ideas on the subject (...if ever anyone is interested in doing it U_U).

Answer 1

It probably depends on the size of the area where you want to operate your robot.

For me it was always good enough to use equirectangular projection, because for my assumptions "at most 1km large area at most 1000km from where I live" the error always comes up as negligible (I don't remember the value now and I don't have time to calculate it, but my guess would be under 1mm). You should calculate it and decide for yourself.

If your robot will operate on a significantly larger part of the Earth and would have problems with this kind of distortion, I guess that it would be worth to invest into a proper 3D world model instead of fighting with projection deformations.